Most fatty acids, important for development and especially the Omega-3 fatty acids for the brain development are transferred in the third trimester with means that in the premature infant this transport via the placenta is interrupted and the infant is dependent on the concentrations in breast milk which vary depending on the mother's diet and her stores. It has even been suggested that low Omega-3 would be a cause of premature delivery. Many countries have much higher levels of Omega-3 fatty acids in breast milk than found in Sweden and breast milk substitutions are generally now supplemented with the Long Chained Poly Unsaturated Fatty Acids (LCPUFA). Therefore the supplementation to be given can not be seen to give any risks for the infant. On the contrary, several studies have shown that mother who eat equal to or less than twice fish a week during pregnancy give birth to infants with impaired development.